Carburetor



Sept'. 14 1926.

F. Q..BA| L CARBURET'OR Filed June 30. 1920 a. 9` 7 6 mw 5 2 8 H 6 M mw \\1 9 6 w 0 f2. 9 KJ?" 5 m 2 l l l l l IIM/JIIl/NMM 2 i L l l llalv||||||\l\\\m\|\i uw w". f rmww l l 2 .\.l\l M 1 l 7 ad, 1| 4 0 3 3 5 4 9 3 b 9 a \f 3 w M w w .a a 6 du 9 n m m W @ILM ATTQRNEY.

Patented Sept. 14, 1926.

UNITED sTATEs PATENT oFEicE.

FREDERICK O. BALL, F DETROIT, MICHIGAN, ASSIGNOR T0 BALL AND- BALL CARBU RETOR COMPANY, 0F DETROIT, MICHIGAN, A PARTNERSHIB COMPOSED OF FRED- ERICK 0. BALL AND CORNELIA M.. BALL.

CARBUBETOR.

Application led June 30,

In controlling the fuel supply to carburetors and properly proportioning it to the air flow it has been found desirable to vary the control as` the pressure varies in the manifold, or above the throttle. A leaner mixture may be used with a lower pressure or greater suction effort in th-e manifold but a richer mixture is desired when this pres sure drops and there is a less suction effort.

In carrying out my invention I utilize a system of control wherein the fuel is sprayed into the main air passage and I control the flow of fuel t-o the spray passage by air ducts leading to the spray passage, one of the air ducts leading from above the fuel level andv one from below the fuel level and `one of the air ducts having a greater restriction than the other. By controlling the course of air through these ducts a variation in the flow of fuel to the spray nozzle is secured. Further where the lower air passage to thespray nozzle is below the fuel level and this is the air passage which is utilized at low velocity through the main air passage of the carburetor the pulsations of motors having few cylinders do not interfcre with the regulation because the spray in this air passage has a. greater inertia than the air itself and tends to steady the controlling pressures so as to get a more uniform performance and a more uniform flow of fuel` This controlling of the course of the air to the spray nozzle is preferably accomplished through a mechanism actuated by differences of pressure at the discharge side of the throttle so that the responses in ythe richness of fuel follow the manifold pressui-es.

It is desirable where two stage carburetors (carburetors in which there are a plurality of mixture forming throats brought into play successively and where two are used ordinarily termed primary and secondary throats) are used to provide the suction passage with a fuel delivery device adapted to deliver a proportionally large amount of fuel with the slow air movements through the secondary suction passage and to vary this to a proportionally less amount offuel as the velocity of the air increases. In addition to this it is desirable to momentarily deliver an excess of fuel with the opening of the throttle to the secondary passage so 1920. serial No. 393,076..

as to compensate for the lack of atomizing 66 force and the disturbance to the main carburetor flow through the opening of the secondary suction passage.

The invention, therefore, has for its purpose the carrying out of the desirable features above referred to, that is to say, providing a means of varying the richness of the mixture with varying velocities through the carburetor; providing a carburetor that will operate efficiently under dierent pul- 6B sation conditions; supplying the secondary tiroat of carburetor'of a two-stage carburetor with means for varying the mixture richness and also to provide it with a momentary added quantity of fuel to enrich the fuel at the initial opening of the secondarv carburetor and in connection with the meanus just specified providing a pick-up device in relation to the other features for the primary carburetor.

The invention is illustrated in the accompanying drawings as follows Fig. 1 is a section on the line'l--l in Fig. 2.

Fig. 2 is a section on the line 2 2 in 80 Fig. l.

1 vmarks the main air passage or suction passage of the carburetor, 2 the Venturi tube or restriction ordinarily arranged in the suction passage, 3 the throttle valve of the pri- 85 mary suction passage, 4 a stem on which the throttle valve 3 is mounted, 5 a lever for operating the throttle valve 3, 6 a secondary suction passage, 7 the throttle valve controlling the secondary suction passage, 8 a shaft 90 on which the secondary throttle is mounted,

9 a lever carried by the shaft 8, 10 a spring operating on the lever 9 and holding the throttle valve 7 normally in closed position, and 11 a cam roller on th-e lever 9 engaging 95 an arm 12 on the lever 5, the arm 12 being so arranged relatively to the throttle 3 as to engage the roller 11 to operate thelever 9, and throttle 7 in the late part of the travel of the throttle 3 in its opening movement. 100 The secondary suction passage is provided with the usual Venturi tube 6a.

A constant level fuel reservoir 13 is .in the form of the usual float chamber. The fuel is supplied to the float chamber through the Isupply fitting 14 passing a strainer 15 and is controlled by a valve 16. The valve 16 has a stem 17. The usual spool 18 is arranged on the stem 17. Levers 19 extend from the spool and are operated upon by the floats 20. A float, therefore, opens and closes the valve 16 thus maintaining a constant level in the fioat chamber.

Fuel is delivered from the float chamber by way of a fuel passage 21. The fuel passage 21 leads to a lateral passage 25. The passage 25 leads into an upright passage 26, the bottom of which is closed by a plate 27. A plug 29 is screwed into the passage 26 and has an axial opening 30 and a radial opening 31, these openings forming a restriction in the fuel passage. The openings lead to a spray passage 28 which is an extension of the opening 26 above the plug 29. A nozzle 32 leads from spray passage 28 to the mixture passage. rllhe spray passage has an upright extension 33 which connects with a lean mixture air controlling passage 34. rlhe passage 34 leads into an upright passage 35 which leads to the outer air through a restricted passage 36. rlhe air converts the liquid in this passage in to a spray or emulsion thus reducing its specific gravity to so great an extent as to eliminato the influence of gravity from this point to the delivery through the nozzle to the throat of the carburetor. The part of the passage through which this emulsion is' formed and carried l have designated as thespray passage and the part of the carburetor to which the nozzle leads as the mixture passage. With the air 'passing through the passages just referred to air is delivered above the fuel level.

on the fuel and the fuel level is carried downv the spray passage so as to permit the air when sprayed to pass into the bottom part of the nozzle 32. This is a comparatively lean mixture for two reasons, first, the restriction is not great, and, second, the level' of fuel at the nozzle entrance below the normal fuel level is very slight.

T he rich mixture air passage comprises a lateral passage 37 which communicates with an upright annular passage 38. rlhe annular passage 38 is formed around an extension 39" on a plug 39 screwed into the bottom of the opening 39a. A. plate 38a is arranged in the opening 39fL and has an opening 38h into which the extension 39D extends. By substituting diderent plugs 39 the restriction through the opening 381 maybe varied. It will be noted, therefore, that the air going through the upper or lean air passage sprays the fuel only from a level at the entrance of the nozzle 12 and as this is very little below the fuel level there is no gravity effect whatever. When, however, this pasn sage is shut off and the air passes through the conduit 37 the fuel is sprayed from a point opposite the passage 31 and this increases the effect of gravity. rfhus this change in level aids in increasing the How of fuel.

Lacasse lt will be understood that in the normal operation of the engine the air is delivered through the rich mixture passages, and sprays the fuel in the passage down to the level of the passage 37. A very much richer mixture is, therefore, delivered because the restriction 38b is greater than the restriction 36 which controls the lean mixture passage and also because the fuel level of the spray passage is lowered. The spray in the passages when air is delivered below the fuel level as through the rich mixture passage 37 is heavier and, therefore, has sullicient inertia to operate-correctly when subjected to the pronounced pulsations of motors having few cylinders.

lf it is desired to have an initial excess of fuel on the transfer of the direction of air from the lean air passage 34 to the rich air passage 37 the spray passage as it is constin tuted in connection with the rich air passage 37 may be somewhat enlarged so as to carry a supply of fuel which is immediately delivered through the nozzle when the air begins to pass through the passage 37 and brings the spray level down to the level. of the passage 37.

The device for shifting the flow of air from one air system to the other is controlled preferably as before stated by variations of pressure at the discharge side of the throttle. ln the present invention this is accomplished by using a valve 40. This valve is carried by a stern 41 which terminates in a plunger 42. The plunger 42 operates in a cylinder 43 and the cylinder 43 is connected by a passage 44 with a passage 45 leading to the suction passage at the discharge side of the throttle. lWhen the plunger is in its upper position it seats on a valve seat 46 so as to prevent leakage. A spring 4( tends to force the plunger downwardly and to move the valve 4() so as to cut off the passage 34 from the passage 35. A supplemental valve 4UL operates over the top of the passage 35 and prevents an inflow of air to that passage from its upper end when the valve 40 is closed. The operation of this is as followsz-llhen the manifold pressures are low either from the closing of the throttle or a very rapid movement of the engine the pressure is sufficiently reduced to lift the plunger 42 and with it the valve 4() against the resistance of the spring 47. Air then moves by way of the restriction 36, passages 35, 34 and 33 to the spray nozzle and a com paratively lean mixture is delivered. lil/Then, however, the velocities are low and the pressures above the throttle are comparatively high the preponderance of pressure on the outside of the plunger is less and conscquently the spring-47 acting with gravity on the plunger overcomes the suction effect on the plunger and the plunger drops down so that the valve 40 shuts off the valve 34.

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lltll The air then moves by way of the restriction 38h and the passages 38 and 37 to the spray passage7 the first effect of which is to carry in the excess of liquid in the. spray passage and then to continue spraying fuel giving a richer mixture in the manner hereinbefore described. In order to protect the spring 47 and the stem 41 I provide a tube 48 which is secured to the body of the carburetor and surrounds the stem and spring. The idling bypass extends from the spray passage to a point approximately opposite the throttle when the throttle is closed. A tube 49 is secured in the upper end of the plug 29 and the plug has a radial opening 49a which connects the tube 49 with the spray passage. The tube extends into a passage 50 in the body of the carburetor and a lateral passage 51 leads to suction passage at the point above mentioned. In order to prevent errors in the positioning of the passage 51 relatively to the throttle a slot 52 is provided which removes the immediate entrance of the passage 51 from the edge of the throttle. An air passage 53 leads from the suc'- tion passage to the passage 50 and thisis controlled by a needle valve 54 by means of which the suction effect on the bypass may be controlled and consequently the idling mixture may be controlled.

The fuel supply for the secondary suction passage is as follows -Alateral passage 58 leads from the passage 21 (see Fig. 1). The passage 58 leads to a passage 59, the bottom of which is closed by a plate 60. A plug 61 is arranged in the passage 59 and has a restricted opening 62. A nozzle 63 extends fromthe extension 59a of the passage 59 and enters the Venturi tube 6a of the secondary suction passage. The extension 59a forms a spray passage and an air passage 64 leads to the spray lpassage preferably being provided with a storage well 65 and a restricted vent 66. The operation of this fuel delivery device of the secondary suction passage is as follows: With the initial opening of the secondary throttle 7 and a slow velocity of air the delivery of fuel through the nozzle 63 is incident to the enl tire suction effect of the air passing through the Venturi tube.

This continues until "there is a sufficient suction effect to empty portionally large amount of fuel is, there-y fore, delivered with an initial opening of the throttle while the fuel is delivered directly'as fuel from the nozzle and after the secondary throttle is open so that there is a high velocity the quality is immediately brought down to a leaner mixture which follows and continues in proportion to the larger requirements of the secondary carburetor.

What I claim as new is 1./ In a carburetor, the combination of a suction passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; a fuel conduit leading from the reservoir to the spray passage; a rich mixture air passage leading to the spray passage; and al lean mixture air passage leading to the spray passage at a point above the rich mixture passage. 1

2. In a carburetor, the combination of a suction passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; a fuel conduit leading from the reservoir to the spray passage; a rich mixture air passage leading to the spray passage; a lean mixture air passage leading to the spray passage at a point above the rich mixture passage; and means controlling the course of air through said rich and leanl mixture air passages.

.3. In a carburetor, the combination of a suction passage; a throttle in the suctionV passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; a fuel conduit leading from the reservoir to the spray passage; a rich mixture air passage leading to the spray passage; a lean mixture air passage leading to the spray passage at a point above the rich mixture passage; means controlling the course of air through said rich and lean mixture air passages; and devices controlled by the pressure at the discharge side of the throttle controlling said means.

4. In a carburetor, the combination' of a suction passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; a fuel conduit leading from the reservoir tothe spray passage; a rich mixture ai/r passage leading to a level in the spray passage below the normal fuel level;`and a lean mixture air passage leadf ing to the spray passage from a point above the normal fuel level.

5. In a-carburetor, the combination of a nov suction passage; a constant level fuel reser' voir; a spray passage feeding into the suction passage; a fuel conduit leading from the reservoir to the spray passage; a rich mixture air passage leading to thespray passage; a lean mixture air passage lead/ing to the spray passage ata point above the rich mixture passage; means controllingl the course of air through said rich and lean mixtureair passages comprising a valve operating on one of said mixture passages; and devices for actuating said valve.

G. In a carburetor, the combination of a suction passage; a throttle in the suction u passage; means controlling the course of air through said rich and lean lrr'iixture air passages comprising a valve; and devices controlled by the pressures at the discharge side of the throttle controlling said valve.

7. In a carburetor, the combination of a suction passage; a throttle in the suction passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; a fuel conduit leading from the reservoir to the spray passage; a lower air passage leading to the spray passage; an upper air passage leading to the spray passage; a valve for closing the upper air passage; a stem on the valve; a plunger on the stem; a cylinder in whichthe plunger operates; and a connection between the cylinder and the suction passage at the discharge side yof the throttle.

8. In a carburetor, the combination of a suction passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; a fuel conduit leading from the reservoir to the spray passage; a rich mixture air passage leading to the spray assage; and a lean mixture air passage eadiug to the spray passage, the rich mixture passage being more restricted than the lean mixture passage.

9. In a carburetor, the combination of a suction passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; -a fuel conduit leading from the reservoir to the spray passageaabrich 'mixture air passage leading to the *spray passage; and a lean mixture air passage leading to the spray passage at a point above the rich mixture4 air passage, the rich mixture air passage being more restricted than the lean mixture air passage.

10. In a carburetor, the combination of a suction passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; a fue conduit leading from -the reservoir to ithe spray passage; a rich mixture air passage leading to the spray passage; a lean mixture air passage leading lmy hand.

to the spray passage at a point above the rich mixture passage; and means controlling the course of air'through said rich and lean mixturev air passages, said spray passage being enlarged above the level of the rich mixture air passage to provide an initial excess of fuel'when air is passed through the rich mixture air passage.

1l. In a carburetor, the combination of a suction passage; a throttle in the suction passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; a fuel conduit leading from the reservoir to the spray passage; a plug in the fuel conduit forming a restriction; a controlling passage arranged beside the spray passage; lateral connections between the spray passage and the controlling passage, these connections being at different levels; means for restricting the passage at the lower level; a valve operating in the controlling passage and controlling the connection at the upper level; and means controlled by variations of pressure at the discharge side of the throttle controlling said valve. y

12. In a carburetor, the combination of a primary suction passage With means for deivering fuel and air thereto; a secondary suction passage; throttles controlling said passages to open the secondary passage after the opening of the primary passage; and a fuel delivery device for the secondary suction passage controlled by conditions in the secondary suction passage and delivering a comparatively large proportion of fuel during the slow movement of air through the secondary suction passage and a comparatively small proportion of fuel When the velocity of air in the secondary suction passage is rapid.

13. In a carburetor, the combination of a suction passage; a constant level fuel reservoir; a spray passage feeding into the suction passage; a fuel conduit leading'from the reservoir tothe spray passage; a rich mixture air passage leading to the spray passage; there being an enlargement for retaining a supply of fuel which is carried forward Withthe initial movement of air through the rich mixture passage; a lean mixture air passage leading to the spray passage; and means controlhng the course of air through said rich and lean mixture air passage.

In testimony whereof I have hereunto set FREDERICK O. BALL.

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